Lubricating oil composition



Patented Apr 29, l94l LUBRICATING OIL COMPOSITION Matthew Fairlie, Hammond, IndL, assignor to Sinclair Refining Company, New York, N. Y., a

corporation of Maine N Drawing. Application May 1, 1939, Serial No. 271,168

Claims.

My invention relates to improvements in 00111 pounded petroleum lubricating oils.- The improved lubrlcating oil compositions of my invention consist essentially of a petroleum lubricating oil and chloro calcium phenyl stearate, or chloro calcium phenyl stearate together with calcium phenyl stearate, or chloro calcium phenyl stearate together with phenyl stearic acid, or a mixture of chloro calcium phenyl stearate and calcium phenyl stearate together with phenyl stearic acid, in amount, or amounts, insumcient materially to alter the normal liquid character of the petroleum lubricating oil itself, 05-25% on the oil for example.

The term petroleum lubricating oils, is intended to refer herein to lubricating oils of petroleum origin having viscositiesupwards of 50 -70 seconds at 100 F. Saybolt Universal.

The trend of development in internal combustion engines has imposed increasing iburdens upon the oils used for their lubrication, particu larly with respect to operating temperatures and pressures, At present, the Diesel type of engine probably represents extreme requirements in both of these respects, but it is not alone in the imposition of severe burdens upon the lubricating oil used. The usual operating life of a lubricating oil, in such service, is determined in large measure, by its thermal stability and by its physical capacity to continue functioning as a lubricant at the high temperatures and, high pressures encountered. One measure of thermal stability is resistance to oxidation and the consequent tendency to form sludge, but in another aspect the efiect of thermal instability is determined not only by the extent of oxidation or decomposition but also by the character of the productsof such decomposition or oxidation and by the extent and location, within the engine, of deposits of such products.

The improved lubricating oil compositions of my invention have a higher film strength than the petroleum oils of which they are compounded. In. addition they have a high solvent capacity for sludge of the character formed by oxidation of petroleum lubricating oils, and perhaps eleven greater importance the properties of rendering deposits of sludge and "carbon within the engine soft and friable rather than hard and coherent and of disintegrating and removing such deposits as an incident of the normal operation of the engine.

In the Diesel type of engine, for example, the high temperatures to which the lubricating oil is subjected, particularly at the top of the stroke, frequently cause deposition of sludge and carbonization in the groove for and behind one or more of the piston rings. Consequent sticking of the rings rapidly deprives the piston and cylinder wall of proper lubrication inducing excessive wear and, frequently, scoring of the cylinder wall. The formation of such carbon deposits, hard enough and coherent enough to involve sticking of the rings, is materially retarded, if not avoided, by the use of the improved lubricating oil compositions of my in vention.

I am aware of the fact that calcium phenyl stearate has been proposed as a component of liquid lubricating oil compositions suitable for use in the Diesel type of internal combustion engine as disclosed in Vobach Patent No. 2,081,075, granted May 18, 1937. I am also aware of the fact that chlorine derivatives of various organic soaps in which the chlorine is attached to the organic radical have been proposed as addition agents for lubricating compositions to improve the film strength. However, I have found that most chlorine derivatives of calcium phenyl stearate in lubricating oil compositions are thermally unstable. Such compositions change color when heated to about 380 F. and precipitation of calcium chloride occurs when the mixture is further heated to temperatures varying from 470 F. up to 670 F. The calcium chloride thus precipitated acts as an abrasive. the lubricating oil compositions of the present invention are heated, the color change occurs but no precipitation follows even when the mixture is heated up to 670 F.

Chloro calcium phenyl stearate for use in compounding the improved lubricating oil compositions of my invention may be prepared by various methods. One advantageous method comprises reacting calcium hydroxy-chloride with either pure or commercial phenyl stearic acid, as by digesting the phenyl stearic acid in a benzol solution at -200 F. for three hours with 10% excess of calcium hydroxy-chloride, then-filtering through Supercel filter-aid and When the first ring" groove.

was clean. tion adequately lubricated the moving parts of lubricating oil in proportions ranging from about 0.5% up to about 2.0% or 2.5% by weight on the oil, or, if desired, the lubricating oil compositions of my invention may be compounded by adding calcium hydroxy-chloride to a solution of phenyl stearic acid in the petroleum lubricating oil to be embodied in the eventual composition.

Fur

The following specific example will serve to i illustrate one method of preparing a lubricating oil composition embodying my invention.

Calcium hydroxy-chloride first was prepared by dissolving 1610 grams of calcium chloride in 3670 cc. of water. To this solution was added 160 grams of hydrated lime (Ca(OH)z). This mixture was digested minutes at 180-200" F.

The mixture was then filtered hot and 1060 cc.

of water was distilled from the filtrate. The distillation residue was chilled to F. overnight and then filtered cold. 135 grams of a. precipitate consisting principally of calcium hydroxychloride was recovered from this filtrate. Analysis of the precipitate showed it contained 30.2% calcium and 32.2% chlorine corresponding approximately to 55.4% calcium hydroxychloride (Ca(0H)Cl) and 17.2% calcium chloride.

. A blend comprising approximately 1 of chloro calcium phenyl stearate in a petroleum oil was preparedin the following manner:

284 grams of commercial phenyl stearic acid were dissolved in 3 liters of a South Texas pale oil having a viscosity approximating500 seconds at F. Saybolt Universal and grams of the calcium hydroxy-chloride precipitate prepared as above described then were, added. This was the amounttheoreticallyneeded to neutralize 284 grams of phenyl stearic acid. This solution was slowlyv heated to 320 F. with stirring and then diluted to 7% gallons by further additions South Texas oil South +l%% chloro Texas calcium phenyl oil steer-ate mi;-

ture

Gravity 20. 2 20. 1 Flash 385 380 Fire; 440 441] Viscosity at 100 F. Saybolt Umversal 505 52l Viscosity at 210 F. Saybolt Universal 523. 7 54. 5 o --l0 --l0 Carbon rcslduc 0. 042 0. 205 Ash 0.0 0. Acid number 0.025 0. 250 Saponification numbcr .0. 54 1.48 Percent calcium 0. 087 Percent chlorine 0. 062

A portion of the lubricating 011 composition prepared as above described was hydrolyzed with hot dilute nitric acid, washed with distilled water, and filtered dry. Analysis of the hydrolyzed oil showed it to contain .0005% calcium and no chlorine. The hydrolyzed oil had an acid number of 3.4. The absence of chlorine from the hydrolyzed oil sample shows that the chlorine in the original blend had been present as the half soap rather than as a chlorinated organic radical.

Expressed as a percentage of the finished blend, the approximate composition of the addition agent in the above-described example, as determined by calculation from the analysis of calcium, chlorine and acid, would be as follows:

' Per cent Chloro calcium phenyl stearate 0.759 Calcium phenyl 'stearate 0.322 Phenyl stearic acid 0.145

The homologues of phenyl stearic acid, for example, tolyl stearic acid,"xylyl stearic acid, naphbe treated withcalcium hydroxyechloride in a similar manner to produce the corresponding substituted calcium chlorides. These chlorine derivatives of the calciumsalts of the aryl stearic acids, with the chlorine attached to thecalcium rather-than to the aryl stearic acid radigoal and with the ratio of chlorine to calcium at a of the South Texas pale oil. The diluted blend was heated to F, and filtered through Supercel filter-aid. .The resultant lubricating oil composition is'an embodiment of my invention.

The Indiana oxidation test of this composition was 22% hours as compared to 14 hours. for the petroleum lubricating oil alone.

pared to 14 pounds for the petroleumlubricatsubstantially free 'from sludge and carbon deposits. Atthe end oi the test'the pistonkw'asy, v

This Indiana oxidation test is described in the .S. A. E. ur1-; 1 hal 34, 172-173 (1934). The Timkenjbreak' down i test of this composition was 16 'f'p'oun'dsas com "value not exceeding unity, generally appear to be useful for the purposes of my invention.

I claim: 7 1. A liquid lubricating oil composition comprising a petroleum lubricating oil and chloro calcium phenyl .stearate in'which the chlorine is attached to the calcium.

free from sludgeand carbondeposits except .fora

light depositconfined to 'the crown end part: of

Except for patches of easily removable oil sootoverportions of the Throughout this test the composithe engine. I

' The propertiesof this particular lubricating oil composition, as compared to:that of the pe- 2. A ,liquid lubricating oil composition comprising a petroleum lubricating, oil, chloro calv ciumrphenyl stearate in whichhthe chlorine is attached tothe calcium and] calcium phenyl 'stearate.

3. A liquid lubricating oil composition com- "prising a petroleum lubricating oil chloro cal- 'cium phenyl stearate inwhich the chlorine is attached to the calcium and phenyl stearic acid. 4.. A liquid lubricating oil-composition comprising a petroleum lubricating oil, chloro calnciurn phenyl' stearate in which .the chlorine-- is attached to thecalcium, calcium and phenyl"stearic acid. ring lands and plug recesses the piston surface -5. A liquidlubricating -oil composition Qco prising a petroleum. lubricating oil and a ch ro derivative of the calcium salt of an aryl stearic acid in vwhichthe ratio of chlorine to calcium does not exceed. unity and in which the chlorine is MATTHEW FAIIYRLIE.

phenyl stearate, 

